1. Field of the Invention
This invention relates to water meters and is particularly directed to water meters in which the main case is formed of plastic material.
2. Description of the Prior Art
Conventional water meters typically are comprised of a main case which encloses a compartment into which a measuring chamber is received through a suitable opening in the case. A closure member is provided to close the opening in the main case and retain the measuring chamber in the compartment. Normally, the measuring chamber which is generally circular shaped in plan, has a downwardly facing seating surface which is received on a corresponding upwardly facing seating surface in the main case so that when the measuring chamber is seated on the upwardly facing seating surface in the main case, the inlet chamber is thereby isolated from the outlet chamber. As will be explained in more detail hereinafter, the prior art utilizes an upwardly facing seating surface within the main case which is a complete circle which corresponds and mates with the downwardly seating surface on the measuring chamber which likewise is a complete circle. However, in order to form the complete seating surface in a complete circle as will be explained in more detail below, it is necessary to provide an undercut in the main case which requires the use of a core with the main case mold thereby increasing the cost of the mold and the cost of the molding procedure. Alternatively, the undercut may be avoided in such cases by simply filling the undercut space with plastic material from which the main case is formed. This however adds significant cost to the main case.